アブストラクト（29巻3号：神奈川歯学）

神奈川歯学

Japanese

Title　： Porphyromonas gingivalisにおける形質転換系の確立に関する研究
Subtitle　： 原著
Authors　： 崎岡雅仁, 吉本尚, 梅本俊夫
Authors（kana）　：
Organization　： 神奈川歯科大学口腔細菌学教室
Journal　： 神奈川歯学
Volume　： 29
Number　： 3
Page　： 227-237
Year/Month　： 1994 / 12
Article　： 原著
Publisher　： 神奈川歯科大学学会
Abstract　： 「緒言」 Porphyromanas gingivalis(以下, P.g.と略す)は歯周炎の患者の歯周ポケットから高頻度で分離される口腔常在のグラム陰性嫌気性桿菌で, 血液寒天培地上で黒色の集落を形成する. 同菌は成人性歯周病の主要な病原細菌と考えられており, その実験的発症も確認されている. しかし, 同菌の病原性に関係する因子として挙げられているものとしては, プロテアーゼ, コラゲナーゼ, 血球凝集素, 内毒素, 歯周組織への付着に関与する因子などの多岐にわたるため, それらの個々の客観的な評価が困難なものになっている. 遺伝子のクローン化等の分子遺伝学的なアプローチは前述の問題解決に極めて有効な技法と考えられ, これまでにもP.g.の遺伝子のクローン化の報告は少なくない. しかし, これまでのクローン化実験は全て大腸菌を宿主とする系で行われており, 当然のことながら, 遺伝子の発現も異菌種でのものを観察しているに過ぎない.
Practice　： 歯科学
Keywords　： Porphyromonas gingivalis, 形質転換, 制限酵素, プラスミド

English

Title　： Study on Establishment of Transfromation System for Porphyromonas gingivalis
Subtitle　：
Authors　： Masahito SAKIOKA, Hisashi YOSHIMOTO, Toshio Umemoto
Authors（kana）　：
Organization　： Department of Oral Microbiology, Kanagawa Dental College
Journal　： Kanagawa Shigaku
Volume　： 29
Number　： 3
Page　： 227-237
Year/Month　： 1994 / 12
Article　： Original article
Publisher　： Kanagawa Odontological Society
Abstract　： Porphyromonas gingivalis (P.g.) has been generally thought that its transformation by plasmid DNA is impossible. The reason for it was elucidated in this study to be attributable to the presence of restriction enzyme(s) in this species, because transformation was possible when it was tried using plasmid DNAs extracted from the P.g. strains itself. Upon this knowlege, we then tried to obtain a mutant that lacks the restriction enzyme, usable as a recipient strain for transformation experiments. For this, attempts of transformation of strains that had been mutagenized with N-metyl-N'-nitro-N-nitrosoguanidin (NTG) with pE5-2 DNA were performed, and the transformants (erythromycin resistant colonies) thus obtained were cultured in the absence of the antibiotic to allow the plasmid segregation. By this means some strains that exhibited a capacity of incorporating foreign DNAs could be obtained. Subsequently, we made further efforts to find plasmids that can replicate and be maintained stably in P.g. cells. The only known plasmid pE5-2 that can be transferred into P.g. cells by either conjugation or transformation is extremely unstable in this species; we presume that Bacteroides eggerthii, in which the rep gene of pE5-2 originated, is rather distant from P.g. A rep gene from a plasmid of a closer species would likely increase the stability. In this respect, we employed several recombinant plasmids that were constructed by ligating fragments of the plasmids detected from the black-pigmented oral anaerobic species and the erythromycin-resistnce fragment of pE5-2. Among them, we could successfuly found a plasmid, pYH400, a recombinant with the rep gene of a plasmid from Porphyromanas asac-charolytica, which could be maintained in the P.g. cells very stably. It would possibly be usable as a cloning vector for this species.
Practice　： Dentistry
Keywords　： Porphyromonas gingivalis